Merge pull request #41 from kreuzwerker/feat/add-charset

feat: add charset flag

README.md

@@ -20,6 +20,7 @@ Optionally, `ep` can:
 * dry-run (`-d` flag): output to stdout instead of replacing values inline
 * strict (`-s` flag): refuse to fallback to default values
 * verbose (`-v` flag): be verbose about it's operations
+* charset (`-c` flag): specify a custom charset to replace variables. Example: `/usr/local/bin/ep -c iso8859-1 *.conf`
 
 `ep` can also `exec()` another command by passing
 

bin/ep.go

@@ -7,6 +7,7 @@ import (
 	"syscall"
 
 	"github.com/kreuzwerker/envplate"
+	_ "github.com/paulrosania/go-charset/data"
 	"github.com/spf13/cobra"
 	"github.com/yawn/doubledash"
 )
@@ -27,6 +28,7 @@ func main() {
 		dryRun  *bool
 		strict  *bool
 		verbose *bool
+		charset *string
 	)
 
 	root := &cobra.Command{
@@ -38,9 +40,10 @@ func main() {
 		Run: func(cmd *cobra.Command, args []string) {
 
 			var h = envplate.Handler{
-				Backup: *backup,
-				DryRun: *dryRun,
-				Strict: *strict,
+				Backup:  *backup,
+				DryRun:  *dryRun,
+				Strict:  *strict,
+				Charset: *charset,
 			}
 
 			if err := h.Apply(args); err != nil {
@@ -67,6 +70,7 @@ func main() {
 	dryRun = root.Flags().BoolP("dry-run", "d", false, "Dry-run - output templates to stdout instead of inline replacement")
 	strict = root.Flags().BoolP("strict", "s", false, "Strict-mode - fail when falling back on defaults")
 	verbose = root.Flags().BoolP("verbose", "v", false, "Verbose logging")
+	charset = root.Flags().StringP("charset", "c", "", "Output charset")
 
 	if err := root.Execute(); err != nil {
 		log.Fatalf("Failed to start the application: %v", err)

envplate.go

@@ -1,10 +1,13 @@
 package envplate
 
 import (
+	"bytes"
+	"fmt"
 	"os"
 	"path/filepath"
 	"regexp"
 
+	"github.com/paulrosania/go-charset/charset"
 	"github.com/yawn/envmap"
 )
 
@@ -14,9 +17,10 @@ const (
 )
 
 type Handler struct {
-	Backup bool
-	DryRun bool
-	Strict bool
+	Backup  bool
+	DryRun  bool
+	Strict  bool
+	Charset string
 }
 
 var exp = regexp.MustCompile(`(\\*)\$\{(.+?)(?:(\:\-)(.*?))?\}`)
@@ -85,7 +89,12 @@ func (h *Handler) parse(file string) error {
 				errors = append(errors, Log(ERROR, "Tried to escape '%s', but was no escape sequence", content))
 			}
 
-			return escaped
+			encodedValue, err := convertToCharset(escaped, h.Charset)
+			if err != nil {
+				errors = append(errors, Log(ERROR, "Tried to convert string '%s' to charset '%s'  but an error ocourred: %v", encodedValue, h.Charset, err))
+				return value
+			}
+			return encodedValue
 
 		}
 
@@ -112,7 +121,12 @@ func (h *Handler) parse(file string) error {
 			value = esc[:len(esc)/2] + value
 		}
 
-		return value
+		encodedValue, err := convertToCharset(value, h.Charset)
+		if err != nil {
+			errors = append(errors, Log(ERROR, "Tried to convert string '%s' to charset '%s'  but an error ocourred: %v", encodedValue, h.Charset, err))
+			return value
+		}
+		return encodedValue
 
 	})
 
@@ -135,20 +149,42 @@ func (h *Handler) parse(file string) error {
 
 		}
 
-		mode, err := filemode(file)
-
-		if err != nil {
+		if err := saveFile(file, parsed, h.Charset); err != nil {
 			return err
 		}
 
-		if err := os.WriteFile(file, []byte(parsed), mode); err != nil {
-			return err
-		}
+	}
+
+	return nil
 
+}
+
+func saveFile(file string, parsed string, cs string) error {
+	mode, err := filemode(file)
+	if err != nil {
+		return err
+	}
+
+	if err := os.WriteFile(file, []byte(parsed), mode); err != nil {
+		return err
 	}
 
 	return nil
+}
+
+func convertToCharset(data string, charSet string) (string, error) {
+	if charSet == "" {
+		return data, nil
+	}
 
+	buf := new(bytes.Buffer)
+	w, err := charset.NewWriter(charSet, buf)
+	if err != nil {
+		return "", err
+	}
+	fmt.Fprintf(w, data)
+	w.Close()
+	return buf.String(), nil
 }
 
 func capture(s string) (esc, key, sep, def string) {

go.mod

@@ -13,6 +13,7 @@ require (
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/paulrosania/go-charset v0.0.0-20190326053356-55c9d7a5834c // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect

go.sum

@@ -197,6 +197,8 @@ github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJ
 github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/modern-go/reflect2 v1.0.1/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/pascaldekloe/goe v0.0.0-20180627143212-57f6aae5913c/go.mod h1:lzWF7FIEvWOWxwDKqyGYQf6ZUaNfKdP144TG7ZOy1lc=
+github.com/paulrosania/go-charset v0.0.0-20190326053356-55c9d7a5834c h1:P6XGcuPTigoHf4TSu+3D/7QOQ1MbL6alNwrGhcW7sKw=
+github.com/paulrosania/go-charset v0.0.0-20190326053356-55c9d7a5834c/go.mod h1:YnNlZP7l4MhyGQ4CBRwv6ohZTPrUJJZtEv4ZgADkbs4=
 github.com/pelletier/go-toml v1.9.3/go.mod h1:u1nR/EPcESfeI/szUZKdtJ0xRNbUoANCkoOuaOx1Y+c=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/sftp v1.10.1/go.mod h1:lYOWFsE0bwd1+KfKJaKeuokY15vzFx25BLbzYYoAxZI=